Reducing the size of history files and disk usage

By default, SSM persists all history attributes, but to reduce the size of history files and to save disk usage, you can minimize this to only basic attributes. The less attributes you specify (that is, basic versus full attributes), the better the SSM performance.

About this task

You can tune the amount of task and session attributes that the IBM® Spectrum Symphony session manager (SSM) should persist, to disk, for an application's history. Do so by configuring the SD_LIST_TASK_HISTORY_ATTRIBUTES and SD_LIST_SESSION_HISTORY_ATTRIBUTES session director environment variables in the sd.xml file. The session director then passes the values in these environment variables to SSM, and SSM persists application task and session history files, for the attributes specified in the environment variables.

Note: This configuration is supported for historical data for IBM Spectrum Symphony workload; it does not change MapReduce workload historical data.

Procedure

Open the session director service file (sd.xml) for editing.
Add the SD_LIST_TASK_HISTORY_ATTRIBUTES and SD_LIST_SESSION_HISTORY_ATTRIBUTES environment variables and set the value to BASIC or basic.
For example:
```
<ego:EnvironmentVariable name="SD_LIST_TASK_HISTORY_ATTRIBUTES">BASIC</ego:EnvironmentVariable>
<ego:EnvironmentVariable name="SD_LIST_SESSION_HISTORY_ATTRIBUTES">BASIC</ego:EnvironmentVariable>
```
For details on these environment variables and settings, see Session director environment variables.
For a list of the basic history attributes that SSM persists to disk, see Application history task and session attributes persisted by the SSM.